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Featured researches published by Barrett W. Jeffers.


Journal of the American College of Cardiology | 2008

Circulating Lipid Hydroperoxides Predict Cardiovascular Events in Patients With Stable Coronary Artery Disease : The PREVENT Study

Mary F. Walter; Robert F. Jacob; Rebekah E. Bjork; Barrett W. Jeffers; Jan Buch; Yoshiko Mizuno; R. Preston Mason

OBJECTIVES This study was designed to determine the predictive value of lipid hydroperoxide (LOOH) levels for adverse cardiovascular outcomes in patients with stable coronary artery disease (CAD). BACKGROUND Oxidative modification of circulating lipids contributes to inflammation and endothelial dysfunction, which are hallmark features of atherosclerosis. A serum biomarker of oxidation is LOOH, which is a primary product of fatty acid peroxidation. METHODS Serum LOOH levels were measured and correlated with clinical events over a 3-year period in 634 patients with angiographic evidence of CAD. RESULTS Baseline LOOH levels in the highest quartile were associated with hazard ratios of 3.24 (95% confidence interval [CI] 1.86 to 5.65; p = 0.0001) for nonfatal vascular events (n = 149), 1.80 (95% CI 1.13 to 2.88; p = 0.014) for major vascular procedures (n = 139), and 2.23 (95% CI 1.44 to 3.44; p = 0.0003) for all vascular events and procedures. Baseline LOOH levels correlated with serum levels of soluble intercellular adhesion molecule-1 (p = 0.001) and thiobarbituric acid reactive substances (p = 0.001) as well as the mean percent change in stenosis for large segments >50% stenosed (p = 0.048). A multivariate proportional hazards model, adjusted for traditional risk factors and inflammatory markers, showed an independent effect of LOOH on nonfatal vascular events, vascular procedures, and all events or procedures. Amlodipine treatment was associated with reduced cardiovascular events and changes in LOOH levels compared with placebo. CONCLUSIONS Elevated LOOH levels were predictive of nonfatal vascular events and procedures in patients with stable CAD, independent of traditional risk factors and inflammatory markers.


Clinical Therapeutics | 2014

Pharmacokinetics of a Novel Orodispersible Tablet of Sildenafil in Healthy Subjects

Bharat Damle; Gregory Duczynski; Barrett W. Jeffers; Penelope Crownover; Alastair Coupe; Robert R. LaBadie

BACKGROUND Sildenafil citrate is indicated for the treatment of erectile dysfunction. An orally disintegrating tablet (ODT) of sildenafil citrate has been developed for the benefit of patients who have difficulty swallowing solid dosage forms. OBJECTIVE The main goal of this study was to evaluate the bioequivalence of sildenafil ODT with and without water versus marketed sildenafil oral film-coated tablets. A secondary objective was to evaluate the effects of a high-fat meal on the pharmacokinetics of sildenafil ODT. METHODS The bioequivalence study of sildenafil ODT given with and without water versus marketed sildenafil citrate film-coated oral tablets was conducted in 36 subjects. In a food-effect study, the effect of a standard high-fat meal on the pharmacokinetics of sildenafil ODT was evaluated in 12 subjects. Both studies were randomized, open-label, crossover, single-dose (50 mg) studies in healthy men aged ≥45 years. Plasma samples were collected for 14 hours postdose, and pharmacokinetics were determined by using noncompartmental analyses. RESULTS All subjects in both studies were Asian males between the ages of 45 and 69 years. Sildenafil ODT without water was bioequivalent to the marketed sildenafil film-coated oral tablet as the 90% CI for the ratio of geometric means of Cmax, AUC0-∞, and AUC0-last were contained within equivalence limits (80%-125%). When sildenafil ODTs were given with water, the 90% CIs for sildenafil AUC0-∞ and AUC0-last were contained within the range of 80% to 125%; however, the 90% CI for sildenafil Cmax was not (79.76-92.78). This difference in Cmax is unlikely to have any clinically meaningful impact. High-fat meals reduced the rate but not the extent of absorption of sildenafil. Mean Cmax was reduced by 59%, and median Tmax was delayed from 0.625 hour (fasting) to 4 hours (high-fat meal). However, AUC values were comparable between fed and fasted treatments. CONCLUSIONS Sildenafil ODT, given with or without water, provides equivalent systemic exposure compared with marketed sildenafil film-coated oral tablets, thus offering a convenient alternative method of administration. Considering the results of the food-effect study, sildenafil ODT should be taken on an empty stomach. ClinicalTrials.gov identifiers: NCT01254383 (bioequivalence) and NCT01254396 (food effect).


American Journal of Therapeutics | 2015

A Systematic Review on the Efficacy of Amlodipine in the Treatment of Patients With Hypertension With Concomitant Diabetes Mellitus and/or Renal Dysfunction, When Compared With Other Classes of Antihypertensive Medication.

Barrett W. Jeffers; Jeffery Robbins; Rahul Bhambri; Dalia Wajsbrot

The long-term cardiovascular (CV) effects of calcium channel blockers, with special focus on amlodipine, were compared with other classes of antihypertensive medications in high-risk hypertensive patient subgroups. A systematic literature review and meta-analysis was undertaken of 38 unique randomized, active-controlled, parallel-group trials comparing amlodipine/calcium channel blockers with diuretics, &bgr;-blockers, &agr;-blockers, angiotensin-converting enzyme inhibitors, or angiotensin II receptor blockers, with ≥6-month follow-up, and which had included assessment of blood pressure (BP) and CV events [all-cause death, CV death, myocardial infarction (MI), stroke, congestive heart failure (CHF), or major CV events (MACE: MI, CHF, stroke, and CV death)], in hypertensive patients (baseline systolic/diastolic BP ≥140/≥90 mm Hg) with either concomitant diabetes and/or renal dysfunction. In hypertensive patients with diabetes, no difference was found for amlodipine versus comparators with respect to all-cause death, CV death, MACE, and MI; a decrease in stroke risk, and an increase in CHF risk, was seen. In hypertensive patients with renal dysfunction, no difference was found for amlodipine versus comparators with respect to all-cause death, CV death, MACE, MI, and CHF; a decrease in stroke risk was seen. Amlodipine was found to be at least as efficacious as all the other classes of antihypertensive agents in reducing systolic and diastolic BP. Long-term control of BP is critical for avoiding complications of hypertension in high-risk patients, particularly CV and cerebrovascular events such as stroke. This analysis has provided evidence that amlodipine is an appealing therapeutic option in the long-term management of hypertension in both diabetic and renal dysfunction patients.


European Heart Journal - Cardiovascular Pharmacotherapy | 2016

Effect of inter-individual blood pressure variability on the progression of atherosclerosis in carotid and coronary arteries: a post hoc analysis of the NORMALISE and PREVENT studies.

Jung-Sun Kim; Sungha Park; Ping Yan; Barrett W. Jeffers; César Cerezo

Aims To investigate the relationship between visit-to-visit blood pressure variability (BPV) and the progression of both carotid and coronary artery disease (CAD). Methods and results Data from two cardiovascular endpoint studies [Norvasc for Regression of Manifest Atherosclerotic Lesions by Intravascular Sonographic Evaluation (NORMALISE) and Prospective Randomized Evaluation of the Vascular Effects of Norvasc Trial (PREVENT)] were analysed separately. Systolic BPV was assessed as within-subject standard deviation of systolic BP across visits from 12-weeks onwards. Follow-up was 24 months (NORMALISE) or 36 months (PREVENT). Any association between BPV and progression of atherosclerosis was assessed using quantitative coronary angiography (QCA), intravascular ultrasound (IVUS), or B-mode ultrasound (depending on study). Patients from NORMALISE (n = 261) and PREVENT (n = 688 for QCA; n = 364 for ultrasound) were stratified within study according to median systolic BPV. No significant difference in change of minimal luminal diameter (by QCA in PREVENT) or change in percent atheroma volume or normalized total atheroma volume (by IVUS in NORMALISE) was detected for subjects with low BPV (BPV < median) compared with high BPV (BPV ≥ median), regardless of treatment. In PREVENT, a significantly greater reduction in maximum carotid intima-media thickness (IMT) (left and right common carotid artery far wall) was observed for patients with BPV < median compared with those with BPV ≥ median [least squares mean difference 0.06 (95% confidence interval 0.01, 0.11); P = 0.0271], after adjusting for treatment, carotid artery segment (left or right), baseline maximum carotid IMT, and other baseline and cardiovascular risk factors/covariates. Conclusions In patients with existing CAD and well-controlled BP, visit-to-visit BPV was not associated with progression of coronary atherosclerosis; however, a significantly greater reduction in maximum carotid IMT was observed for patients with low BPV.


Vascular Health and Risk Management | 2013

Titration of amlodipine to higher doses: a comparison of Asian and Western experience.

Kazuomi Kario; Jeffery Robbins; Barrett W. Jeffers

In this retrospective analysis, data pooled from two Phase III/IV open-label Asian studies were used to quantify the additional blood pressure efficacy achieved when titrating amlodipine from 5 mg to 10 mg in mild/moderate hypertensive patients, and compared to data pooled from three Western studies. The primary efficacy end point was the change from baseline in sitting systolic blood pressure (SBP) and diastolic blood pressure (DBP) to the specified time point (4–8 weeks, depending on the trial). For the Asian analysis (n=174), both mean SBP and DBP were significantly decreased at the final visit (SBP −13.3 mmHg, 95% confidence interval [CI] −15.5 to −11.0; DBP −9.2 mmHg, 95% CI −10.6 to −7.8; both P<0.0001). These results were similar to the Western analysis (n=369; SBP −11.5 mmHg, 95% CI −13.1 to −10.0; DBP −6.3, 95% CI −7.1 to −5.5; both P<0.0001). In summary, titration of amlodipine from 5 mg to 10 mg significantly decreased both SBP and DBP in Asian patients with mild-to-moderate hypertension.


American Journal of Therapeutics | 2017

Efficacy of Calcium Channel Blockers Versus Other Classes of Antihypertensive Medication in the Treatment of Hypertensive Patients With Previous Stroke and/or Coronary Artery Disease: A Systematic Review and Meta-Analysis.

Barrett W. Jeffers; Jeffery Robbins; Rahul Bhambri

Hypertensive patients, such as those with established coronary artery disease (CAD) or those who have suffered a stroke, are at increased risk of morbidity and mortality. This systematic literature review and meta-analysis assesses the long-term effects of calcium channel blockers (CCBs) compared with other classes of antihypertensive medications on major cardiovascular (CV) outcomes in these high-risk subgroups of hypertensive patients. Randomized, active controlled parallel group trials were included if they compared CCBs with &agr;-blockers, &bgr;-blockers, angiotensin II receptor blockers, angiotensin-converting enzyme inhibitors, or diuretics, had a follow-up of ≥6 months, and had assessments of blood pressure (BP) and CV events [all-cause death, CV death, major CV events (myocardial infarction, MI; congestive heart failure, CHF; stroke; and CV death), MI, stroke, or CHF] in patients with baseline systolic/diastolic BP ≥140/≥90 mm Hg with either concomitant previous stroke and/or CAD. The final dataset included 19 publications reporting on 7 unique trials. In hypertensive patients with previous stroke, there was no difference between CCBs and comparators for any CV outcome. In those with CAD, there was no difference for all-cause death, CV death, major CV events, and MI for CCBs relative to comparators; however, a reduction in the risk of stroke and an increase in the risk of CHF were seen. For BP lowering, CCBs were at least as efficacious as comparators. The findings of our systematic review and analysis add to the body of evidence for the use of CCBs for the long-term treatment of hypertension in difficult-to-treat high CV risk populations.


American Journal of Therapeutics | 2011

A large observational study of cardiovascular outcomes associated with atorvastatin or simvastatin therapy in hypertensive patients without prior cardiovascular disease.

JoAnne M. Foody; Amie T. Joyce; Barrett W. Jeffers; Larry Z. Liu; Joshua S. Benner

The objective of this study was to examine whether differences in effectiveness exist between statins in hypertensive patients seen in clinical practice. We assessed cardiovascular (CV) outcomes in hypertensive patients without cardiovascular disease who began therapy with atorvastatin (10 or 20 mg/d) or simvastatin (20 or 40 mg/d) between January 1, 2003, and September 30, 2005, using claims data from 92 US managed care plans in the PharMetrics database. A total of 98,471 hypertensive patients were identified, comprising 74,685 atorvastatin users (mean dose 13.6 mg/d) and 23,786 simvastatin users (mean dose 28.6 mg/d), and followed a median 1.5 years for the occurrence of a first CV event. The crude CV event rates were 2.81 and 3.92 per 100 person-years for atorvastatin and simvastatin, respectively [unadjusted hazard ratio (HR): 0.73; 95% confidence interval (CI): 0.68-0.78, P < 0.001]. After adjusting for clinical and demographic confounders, use of atorvastatin was associated with fewer CV events compared with simvastatin (HR: 0.91; 95% CI: 0.84-0.98, P = 0.009). However, the lipid-lowering efficacy of the 2 statins could not be assessed as patient lipid data were unavailable. In conclusion, hypertensive patients without cardiovascular disease who initiated atorvastatin (10 or 20 mg/d) had a significantly lower risk of subsequent CV events compared with those who initiated simvastatin at doses of similar potency (20 or 40 mg/d). As with all observational studies, the study is subject to certain limitations, and the findings should be regarded as hypothesis generating.


Vascular Health and Risk Management | 2014

Uptitrating amlodipine significantly reduces blood pressure in diabetic patients with hypertension: a retrospective, pooled analysis

Barrett W. Jeffers; Rahul Bhambri; Jeffery Robbins

Diabetic patients with hypertension are approximately twice as likely to develop cardiovascular disease as non-diabetic patients with hypertension. Given that hypertension affects ∼60% of patients with diabetes, effective blood pressure (BP) management is important in this high-risk population. This post-hoc analysis pooled data from six clinical studies to quantify additional BP efficacy achieved when titrating hypertensive diabetic patients from amlodipine 5 mg to 10 mg. Approximately half of the diabetic patients were male (44/98; 44.9%) with a mean (standard deviation [SD]) age of 60.6 (9.6) years and a baseline mean (standard error [SE]) systolic blood pressure/diastolic blood pressure (SBP/DBP) of 150.8 (1.30)/87.5 (0.94) mmHg while on amlodipine 5 mg (159.1 [1.40]/92.6 [0.94] mmHg prior to treatment). In comparison, 350/610 (57.4%) non-diabetic patients were male with a mean (SD) age of 58.7 (11.1) years and baseline mean (SE) SBP/DBP of 150.3 (0.62)/90.9 (0.41) mmHg while on amlodipine 5 mg (160.0 [0.67]/96.2 [0.45] mmHg prior to treatment). Increasing amlodipine from 5 mg to 10 mg lowered sitting SBP by −12.5 mmHg (95% confidence interval (CI): −15.5, −9.5; P<0.0001) and DBP by −6.0 mmHg (−7.4, −4.6; P<0.0001) in diabetic patients; and SBP by −12.4 mmHg (−13.5, −11.3; P<0.0001) and DBP by −7.3 mmHg (−8.0, −6.7; P<0.0001) in non-diabetic patients. In total, 12.0% (95% CI: 6.4, 20.0) of diabetic patients achieved their BP goal versus 46.4% (42.4, 50.4) of non-diabetic patients after titration to amlodipine 10 mg. Overall, 22.0% of diabetic patients experienced 31 adverse events (AEs) and 28.9% of non-diabetic patients experienced 282 AEs. Serious AEs were reported by one (1.0%) diabetic and five (0.8%) non-diabetic patients. In this analysis, increasing amlodipine from 5 mg to 10 mg produced a clinically significant reduction in the BP of diabetic hypertensive patients, similar to non-diabetic patients, highlighting the importance of optimizing amlodipine titration in this high-risk population.


Diabetes Research and Clinical Practice | 2008

A large observational study of cardiovascular outcomes associated with atorvastatin or simvastatin therapy in diabetic patients without prior cardiovascular disease.

JoAnne M. Foody; Amie T. Joyce; Barrett W. Jeffers; Larry Z. Liu; Joshua S. Benner

Analysis of claims data from 46,076 diabetic patients without cardiovascular disease initiating atorvastatin or simvastatin therapy suggested that, after adjusting for demographic and clinical confounders, use of atorvastatin was associated with fewer cardiovascular events versus simvastatin at doses of similar potency (HR 0.88, 95% CI 0.80-0.97, P=0.01).


Journal of Hypertension | 2016

OS 31-05 THE IMPORTANCE OF INTER-INDIVIDUAL BLOOD PRESSURE VARIABILITY ON THE INCIDENCE OF RECURRENT STROKE: A POST HOC ANALYSIS OF ASCOT AND ALLHAT.

Sun Uck Kwon; Dalia Wajsbrot; Bum Joon Kim; Jaseong Koo; Jong Moo Park; Barrett W. Jeffers

Objective: To evaluate differences in blood pressure variability (BPV) between patients who experience a recurrent (secondary) stroke or transient ischemic attack (TIA) compared with patients who do not have recurrent stroke. Design and Method: Data were extracted from the ALLHAT and ASCOT-BPLA databases. BPV was defined as the within-subject standard deviation of systolic BP measurements across visits from 12-weeks (or 3-months [84 days]) onwards. BPV was analyzed using a generalized linear model with terms for treatment, prior stroke, interaction between treatment group and prior stroke, and baseline systolic BP. Incidence of recurrent stroke was analyzed using a Chi-square test. Results: For ASCOT-BPLA, BPV was significantly higher for patients who did (N = 2046) vs. those who did not (N = 16,806) have a prior stroke, within both the amlodipine and atenolol arms (P < 0.01 for both). Of the 2046 patients from ASCOT-BPLA who had a prior stroke/TIA, 252 (12.3%) had a recurrent stroke/TIA. When patients with prior stroke/TIA were analyzed by BPV quartiles, those with high (≥ Q3) vs. low (P = 0.0068). Of the 2,173 patients from ALLHAT with prior stroke, 161 (7.4%) had a recurrent stroke/TIA. When patients with prior stroke/TIA were analyzed by BPV quartiles, the incidence of recurrent stroke was higher in patients with high (≥ Q3) vs. low (P = 0.0134). Conclusions: In these patients at high-risk for secondary stroke, there is some evidence that management of BPV with antihypertensives is important to reduce the risk for recurrent stroke.

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JoAnne M. Foody

Brigham and Women's Hospital

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Joshua S. Benner

University of Pennsylvania

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